In my home town we had two types of lung disease found in miners. Then, we called them Pneumoconiosis and Silicosis. The first was similar to emphysema in that it reduced lung function, partly by 'setting'in the lungs, and the second was caused by the lungs being abraded by stonedust, which was spread liberally to reduce the risk of explosion.
'Bone and blood is the price of coal.'

Coaldust is pretty sterile, and when it gets into a wound, the wound will heal with the coaldust under the skin, leaving a blue tattoo-like mark. It is not so common nowadays, because fewer miners get the dust driven into their skin by an explosion, which was the most common cause in the past.
I was both a miner and an insurance agent in my youth.